Alternator - regulator mismatch?

My battery has been relocated to the trunk, and I use a cable bolted to the frame back there, as the ground. Then I picked up the ground off the body at the front, and bolted it to the engine block.
I then converted my 1968 car to 70-up electronic regulator and
this has been working flawlessly since 1999.
I bolted the regulator to the apron, up where the horn was, and run a very short fieldwire. The horns I threw into the shed, they just get me into too much trouble.
Initially I was using a DC constant voltage regulator but one day it got "stuck" at 18v, so I swapped it out for a generic jobber one that has now worked well ever since about 2002.

I guess probably any alternator could be married to any regulator.
The thing to remember is this;
the regulator "senses" the system voltage off the ignition circuit, and adjusts the alternator output in an inverse relationship to it, until it hits it's preprogrammed hi-limit.
When the regulator senses a low voltage in the ignition circuit, it cranks up the alternator output until it hits the upper limit. If it senses a hi voltage in the ignition circuit, then it cuts back to it's low limit, which could be zero-charge. That device is always targeting a specific voltage that it wants to see, based on it's programming, which is usually between one and two volts above the battery rest voltage, so 13.5 to 14.5 volts.
But if the battery itself has a high internal resistance,or is frozen, then the regulator is gonna command the alternator to work it's heart out trying to jam electrons into it.